#!/usr/bin/perl -w
use strict;

our $select_job;
our $filehandle_in;
our $filehandle_out;

sub Job_selection{
    $select_job = shift;
    open (our $filehandle_in, "<", "input.txt") || die "Can't read input.txt: $!";
    open (our $filehandle_out, ">", "output_$select_job.txt") || die "Can't write output_$select_job.txt: $!";
    #
    #job is done here
    #
    close $filehandle_in;  
    close $filehandle_out;
}

Job_selection("1");
Job_selection("2");


##</code><code>##

Job_selection("1");
Job_selection("2");